Fragile X syndrome is a neurodevelopmental disorder caused by the absence of the mRNA-binding protein fragile X messenger ribonucleoprotein (FMRP). Because FMRP is a highly pleiotropic protein controlling the expression of hundreds of genes, viral vector–mediated gene replacement therapy is viewed as a potential viable treatment to correct the fundamental underlying molecular pathology inherent in the disorder. Here, we studied the safety profile and therapeutic effects of a clinically relevant dose of a self-complementary adeno-associated viral (AAV) vector containing a major human brain isoform of FMRP after intrathecal injection into wild-type and fragile X–KO mice. Analysis of the cellular transduction in the brain indicated primarily neuronal transduction with relatively sparse glial expression, similar to endogenous FMRP expression in untreated wild-type mice. AAV vector–treated KO mice showed recovery from epileptic seizures, normalization of fear conditioning, reversal of slow-wave deficits as measured via electroencephalographic recordings, and restoration of abnormal circadian motor activity and sleep. Further assessment of vector efficacy by tracking and analyzing individual responses demonstrated correlations between the level and distribution of brain transduction and drug response. These preclinical findings further demonstrate the validity of AAV vector–mediated gene therapy for treating the most common genetic cause of cognitive impairment and autism in children.
Hayes Wong, Alexander W.M. Hooper, Hye Ri Kang, Shiron J. Lee, Jiayi Zhao, Chanchal Sadhu, Satinder Rawat, Steven J. Gray, David R. Hampson
Synaptic plasticity impairment plays a critical role in the pathogenesis of Alzheimer’s disease (AD), and emerging evidence has shown that microRNAs (miRNAs) are alternative biomarkers and therapeutic targets for synaptic dysfunctions in AD. In this study, we found that the level of miR-431 was downregulated in the plasma of amnestic mild cognitive impairment (aMCI) and AD patients. In addition, it was decreased in the hippocampus and plasma of APPswe/PS1dE9 (APP/PS1) mice. Lentivirus mediated miR-431 overexpression in the hippocampus CA1 ameliorated synaptic plasticity and memory deficits of APP/PS1 mice, while it didn't affect the Aβ levels. Smad4 was identified as a target of miR-431, and Smad4 knockdown modulated the expression of synaptic proteins including SAP102, and protected against synaptic plasticity and memory dysfunctions in APP/PS1 mice. Furthermore, Smad4 overexpression reversed the protective effects of miR-431, indicating that miR-431 attenuated synaptic impairment at least partially by Smad4 inhibition. Thus, these results indicated that miR-431/Smad4 might be a potential therapeutic target for AD treatment.
Jianwei Ge, Zhiwei Xue, Shu Shu, Linjie Yu, Ruomeng Qin, Wenyuan Tao, Pinyi Liu, Xiaohong Dong, Zhen Lan, Xinyu Bao, Lei Ye, Yun Xu, Xiaolei Zhu
Although thymidylate synthase (TYMS) inhibitors have served as components of chemotherapy regimens, the currently available inhibitors induce TYMS overexpression or alter folate transport/metabolism feedback pathways that tumor cells exploit for drug resistance limiting overall benefit. Here we report a small molecule TYMS inhibitor that i) exhibits enhanced antitumor activity as compared to current fluoropyrimidines and antifolates without inducing TYMS overexpression, ii) is structurally distinct from classical antifolates, iii) extends survival in both pancreatic xenograft tumor models and hTS/Ink4a/Arf null genetically engineered mouse tumor model, iv) and is well tolerated with equal efficacy using either intraperitoneal or oral administration. Mechanistically, we confirm the compound is a multifunctional non-classical antifolate, and using a series of analogues, we identify structural features allowing direct TYMS inhibition while also maintaining the ability to inhibit dihydrofolate reductase (DHFR). Collectively, this work identifies new non-classical antifolate inhibitors that optimize inhibition of thymidylate biosynthesis with a favorable safety profile highlighting potential for enhanced cancer therapy.
Maria V. Guijarro, Patrick C. Kellish, Peter E. Dib, Nicholas G. Paciaroni, Akbar Nawab, Jacob Andring, Lidia Kulemina, Nicholas V. Borrero, Carlos Modenutti, Michael Feely, Elham Nasri, Robert P. Seifert, Xiaoping Luo, Richard L. Bennett, Daniil Shabashvili, Jonathan D. Licht, Robert McKenna, Adrian Roitberg, Robert W. Huigens III, Frederic J. Kaye, Maria Zajac-Kaye
Muscular dystrophies are a group of genetic neuromuscular disorders that involve severe muscle wasting. Transforming growth factor β-activated kinase 1 (TAK1) is an important signaling protein that regulates cell survival, growth, and inflammation. TAK1 has been recently found to promote myofiber growth in the skeletal muscle of adult mice. However, the role of TAK1 in muscle diseases remains poorly understood. In the present study, we have investigated how TAK1 affects the progression of dystrophic phenotype in the mdx mouse model of Duchenne muscular dystrophy (DMD). TAK1 is highly activated in the dystrophic muscle of mdx mice during the peak necrotic phase. While targeted inducible inactivation of TAK1 inhibits myofiber injury in young mdx mice, it results in reduced muscle mass and contractile function. TAK1 inactivation also causes loss of muscle mass in adult mdx mice. By contrast, forced activation of TAK1 through overexpression of TAK1 and TAB1 induces myofiber growth without having any deleterious effect on muscle histopathology. Collectively, our results suggest that TAK1 is a positive regulator of skeletal muscle mass and targeted regulation of TAK1 can suppress myonecrosis and ameliorate disease progression in DMD.
Anirban Roy, Tatiana E. Koike, Aniket S. Joshi, Meiricris Tomaz da Silva, Kavya Mathukumalli, Mingfu Wu, Ashok Kumar
GM3 synthase deficiency (GM3SD) is an infantile-onset epileptic encephalopathy syndrome caused by biallelic loss-of-function mutations in ST3GAL5. Loss of ST3GAL5 activity in humans results in systemic ganglioside deficiency and severe neurological impairment. No disease-modifying treatment is currently available. Certain recombinant adeno-associated viruses (rAAVs) are capable of crossing the blood-brain barrier to induce widespread, long-term gene expression in the central nervous system (CNS), and represent a promising therapeutic strategy. Here, we show that a first-generation rAAV-ST3GAL5 replacement vector employing a ubiquitous promoter restored tissue ST3GAL5 expression and normalized cerebral gangliosides in patient-derived iPSC neurons and brain tissue from St3gal5 knock-out mice, but caused fatal hepatotoxicity when administered systemically. In contrast, a second-generation vector optimized for CNS-restricted ST3GAL5 expression, administered by either intracerebroventricular or intravenous route at postnatal day 1, allowed for safe and effective rescue of lethality and behavior impairment in symptomatic GM3SD mice up to a year. These results support further clinical development of ST3GAL5 gene therapy.
Huiya Yang, Robert Brown, Dan Wang, Kevin A. Strauss, Guangping Gao
Synovial Fibroblasts (SFs) are key pathogenic drivers in Rheumatoid arthritis (RA). Their in vivo activation by TNF is sufficient to orchestrate full arthritic pathogenesis in animal models and TNF blockade proved efficacious for a high percentage of RA patients albeit co-inducing rare but serious side effects. Aiming to find new potent therapeutics, we applied the L1000CDS2 search engine, in order to repurpose drugs that could reverse the pathogenic expression signature of arthritogenic human TNF transgenic (hTNFtg) SFs. We identified a neuroleptic drug, namely Amisulpride, which reduced SFs’ inflammatory potential while decreasing the clinical score of hTNFtg polyarthritis. Notably, we found that Amisulpride function is neither through its known targets Dopamine receptors 2 and 3 and Serotonin Receptor 7, nor through TNF-TNFRI binding inhibition. Through a click chemistry approach, novel potential targets of Amisulpride were identified, which were further validated to repress hTNFtg SFs’ inflammatory potential ex vivo (Ascc3 and Sec62), while phosphoproteomics analysis revealed that treatment altered important fibroblast activation pathways, such as adhesion. Thus, Amisulpride could prove beneficial to patients suffering from RA and the often-accompanying comorbid dysthymia, reducing SF pathogenicity along with its anti-depressive activity, serving further as a “lead” compound for the development of novel therapeutics against fibroblast activation.
Dimitra Papadopoulou, Fani Roumelioti, Christos Tzaferis, Panagiotis Chouvardas, Anna-Kathrine Pedersen, Filippos Charalampous, Eleni Christodoulou-Vafeiadou, Lydia Ntari, Niki Karagianni, Maria C. Denis, Jesper V. Olsen, Alexis Ν. Matralis, George Kollias
Targeted biologic therapies can elicit an undesirable host immune response characterized by the development of antidrug antibodies (ADA), an important cause of treatment failure. The most widely used biologic across immune-mediated diseases is adalimumab, a tumor necrosis factor inhibitor. This study aimed to identify genetic variants that contribute to the development of ADA against adalimumab, thereby influencing treatment failure. In patients with psoriasis on their first course of adalimumab, in whom serum ADA had been evaluated 6–36 months after starting treatment, we observed a genome-wide association with ADA against adalimumab within the major histocompatibility complex (MHC). The association signal mapped to the presence of tryptophan at position 9 and lysine at position 71 of the HLA-DR peptide-binding groove, with both residues conferring protection against ADA. Underscoring their clinical relevance, these residues were also protective against treatment failure. Our findings highlight antigenic peptide presentation via MHC class II as a critical mechanism in the development of ADA against biologic therapies and downstream treatment response.
Teresa Tsakok, Jake Saklatvala, Theo Rispens, Floris C. Loeff, Annick de Vries, Michael H. Allen, Ines A. Barbosa, David Baudry, Tejus Dasandi, Michael Duckworth, Freya Meynell, Alice Russell, Anna Chapman, Sandy McBride, Kevin McKenna, Gayathri Perera, Helen Ramsay, Raakhee Ramesh, Kathleen Sands, Alexa Shipman, the Biomarkers of Systemic Treatment Outcomes in Psoriasis (BSTOP) Study Group, A. David Burden, Christopher E.M. Griffiths, Nick J. Reynolds, Richard B. Warren, Satveer Mahil, Jonathan Barker, Nick Dand, Catherine Smith, Michael A. Simpson
Diabetes is associated with increased risk for kidney and liver diseases, congestive heart failure, and mortality. Urinary glucose excretion using sodium-glucose cotransporter 2 (SGLT2) inhibitors prevents these adverse outcomes. We performed in vivo metabolic labeling with 13C-glucose in normoglycemic and diabetic mice treated with or without the SGLT2 inhibitor dapagliflozin, followed by simultaneous metabolomics and metabolic flux analyses in different organs and the plasma. We found that in diabetes, glycolysis and glucose oxidation are impaired in the kidney, liver, and heart. Treatment with dapagliflozin failed to rescue glycolysis and further inhibited pyruvate kinase activity in the liver. SGLT2 inhibition increased glucose oxidation in all organs; in the kidney, this effect was associated with modulation of the redox state, which may protect against oxidative stress. In addition, diabetes was associated with altered methionine cycle metabolism, evident by decreased betaine and methionine levels, whereas treatment with SGLT2i increased hepatic betaine along with decreased homocysteine levels. mTORC1 activity was inhibited by SGLT2i along with stimulation of AMPK in both normoglycemic and diabetic animals, possibly explaining the protective effects against kidney, liver, and heart diseases. Collectively, our findings suggest that SGLT2i induces metabolic reprogramming orchestrated by AMPK-mTORC1 signaling with common and distinct effects in various tissues with implications for diabetes and aging.
Aviram Kogot-Levin, Yael Riahi, Ifat Abramovich, Ofri Mosenzon, Bella Agranovich, Liat Kadosh, Rachel Ben-Haroush Schyr, Doron Kleiman, Liad Hinden, Erol Cerasi, Danny Ben-Zvi, Ernesto Bernal-Mizrachi, Joseph Tam, Eyal Gottlieb, Gil Leibowitz
TGF-β signaling is crucial for modulating osteoarthritis (OA), and protein phosphatase magnesium–dependent 1A (PPM1A) has been reported as a phosphatase of SMAD2 and regulates TGF-β signaling, while the role of PPM1A in cartilage homeostasis and OA development remains largely unexplored. In this study, we found increased PPM1A expression in OA chondrocytes and confirmed the interaction between PPM1A and phospho-SMAD2 (p-SMAD2). Importantly, our data show that PPM1A KO substantially protected mice treated with destabilization of medial meniscus (DMM) surgery against cartilage degeneration and subchondral sclerosis. Additionally, PPM1A ablation reduced the cartilage catabolism and cell apoptosis after the DMM operation. Moreover, p-SMAD2 expression in chondrocytes from KO mice was higher than that in WT controls with DMM induction. However, intraarticular injection with SD-208, repressing TGF-β/SMAD2 signaling, dramatically abolished protective phenotypes in PPM1A-KO mice. Finally, a specific pharmacologic PPM1A inhibitor, Sanguinarine chloride (SC) or BC-21, was able to ameliorate OA severity in C57BL/6J mice. In summary, our study identified PPM1A as a pivotal regulator of cartilage homeostasis and demonstrated that PPM1A inhibition attenuates OA progression via regulating TGF-β/SMAD2 signaling in chondrocytes and provided PPM1A as a potential target for OA treatment.
Qinwen Ge, Zhenyu Shi, Kai-ao Zou, Jun Ying, Jiali Chen, Wenhua Yuan, Weidong Wang, Luwei Xiao, Xia Lin, Di Chen, Xin-Hua Feng, Ping-er Wang, Peijian Tong, Hongting Jin
Despite advances in ovarian cancer (OC) therapy, recurrent OC remains a poor-prognosis disease. Because of the close interaction between OC cells and the tumor microenvironment (TME), it is important to develop strategies that target tumor cells and engage components of the TME. A major obstacle in the development of OC therapies is the identification of targets with expression limited to tumor surface to avoid off-target interactions. The follicle-stimulating hormone receptor (FSHR) has selective expression on ovarian granulosa cells and is expressed on 50%–70% of serous OCs. We generated mAbs targeting the external domain of FSHR using in vivo–expressed FSHR vector. By high-throughput flow analysis, we identified multiple clones and downselected D2AP11, a potent FSHR surface–targeted mAb. D2AP11 identifies important OC cell lines derived from tumors with different mutations, including BRCA1/2, and lines resistant to a wide range of therapies. We used D2AP11 to develop a bispecific T cell engager. In vitro addition of PBMCs and T cells to D2AP11-TCE induced specific and potent killing of different genetic and immune escape OC lines, with EC50s in the ng/ml range, and attenuated tumor burden in OC-challenged mouse models. These studies demonstrate the potential utility of biologics targeting FSHR for OC and perhaps other FSHR-positive cancers.
Devivasha Bordoloi, Pratik S. Bhojnagarwala, Alfredo Perales-Puchalt, Abhijeet J. Kulkarni, Xizhou Zhu, Kevin Liaw, Ryan P. O’Connell, Daniel H. Park, Daniel W. Kulp, Rugang Zhang, David B. Weiner
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